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Stormy weather and new snow: In the west a high avalanche danger will be encountered in some regions

Stormy weather and new snow: In the west a high avalanche danger will be encountered in some regions

Avalanches can in isolated cases be released in deeper layers. Avalanches can reach medium size. Careful route selection is recommended.

During the last six days there has been snowfall registered everywhere, in northern regions a great deal. The fresh snow and fresh snowdrifts during this period were deposited on top of a shallow but weak old snowpack. The snowpack layering is thereby unfavourable, particularly on west-facing, north-facing and east-facing slopes above 2000 m. On Saturday in the western and the northern regions, additional large-sized snowdrift accumulations are expected to form. As a result of rising temperatures and rainfall, increasingly frequent wet-snow and gliding avalanches can be expected on the northern flank of the Alps below approximately 1800 m more than anywhere else.

In the northern regions, intensive snowfall was registered for a short time as an active cold front moved through on Thursday evening, and the snowfall level descended from 800 m down to low lying areas. On Friday it was predominantly sunny, in the eastern regions still overcast in the morning hours due to high-foglike conditions. Fresh snow: Between Thursday afternoon and the end point of this round of precipitation on Friday morning, the following amounts of fresh snow were registered: - northern flank of the Alps: 15 to 30 cm, from the Reuss into the Glarus Alps: as much as 40 cm; - Lower Valais, remaining parts of the Gotthard region, northern Grisons: 5 to 15 cm; in the other regions of Switzerland, less. Thus, during the last six days the following amounts of fresh snow were registered overall above 1800 m: - northern flank of the Alps from, the Brienz Rothorn into the Alpstein: 100 to 150 cm; 200 cm from place to place in the Glarus Alps; - remaining parts of the northern flank of the Alps, Grisons north of the Anterior Rhine, Prättigau: 60 to 100 cm; - in the other regions of Switzerland, 20 to 60 cm over widespread areas; in the valleys of Visp and in the Upper Engadine, less. Temperature: At midday at 2000 m, -7 °C over widespread areas, and -11 °C in the northeastern regions. Wind: Winds were northwesterly: - in the Jura region blowing at storm strength during the nocturnal hours; - on the Main Alpine Ridge blowing intermittently at strong velocity; - in the other regions of Switzerland, blowing predominantly at light to moderate strength. On Friday night in the western and the northern regions, intensive snowfall is expected to set in. This precipitation will subsequently persist throughout the daytime hours on Saturday. The snowfall level will swiftly ascend to approximately 1400 m, temporarily up to approximately 1800 m in the western regions. In the Upper Valais, the snowfall will persist longer, extending down to the valley floor. In the southern regions and in Grisons, only a small amount of snowfall is anticipated. In the furthermost southern regions it will remain dry. Fresh snow: By Saturday afternoon, the following amounts of fresh snow are expected above approximately 2000 m: - northern flank of the Alps, northern Valais and furthermost western part of Lower Valais: 20 to 40 cm; as much as 70 cm along the French border; - remaining parts of the Valais not including valleys of Visp, Grisons north of Anterior Rhine, northern Prättigau: 15 to 30 cm; - in the other regions of Switzerland, less; in the furthermost southern regions it will remain dry. In the Jura region, 30 to 50 cm of snowfall is expected on the highest summits; below those altitudes, predominantly rainfall is anticipated. Temperature: At midday at 2000 m, 0 °C in the northern regions and -5 °C in the southern regions. Wind: Winds at high altitudes and on the northern flank of the Alps will be blowing at strong to storm strength from westerly directions.

Sunday: On Sunday, skies will be heavily overcast. Snowfall is expected to fall down to low lying areas, but the intensity of the precipitation will slacken off considerably during Saturday night. North of an imaginary Rhine-Rhone line and in the Lower Valais, an additional 20 to 30 cm of fresh fallen snow is expected by Sunday afternoon; along the French border approximately 40 cm. In the furthermost southern regions it will be quite sunny. In the western and the northern regions, avalanche danger levels are expected to increase somewhat on Saturday night. Conditions will be most treacherous in the furthermost western part of Lower Valais, where Danger Level 4 (high) will presumably be reached. During the daytime on Sunday, the frequency of naturally triggered avalanches will diminish, however the situation will remain critical for winter sports enthusiasts in outlying terrain away from secured public ski slopes. In the southern and southeastern regions, avalanche danger levels are not expected to change significantly. Monday: In the northern regions skies will be overcast and a small amount of snowfall is anticipated to fall down to low lying areas. In the inneralpine regions, bright intervals are expected; and in the furthermost southern regions it will be predominantly sunny. Avalanche danger levels will diminish, but with the exception of the southern regions, avalanche conditions in outlying terrain are expected to remain still treacherous.